Fuel cells are devices that generate electricity through electrochemical reactions between fuel gases such as hydrogen and air (oxygen). Fuel cells can directly convert chemical energy into electricity and thus have high power generation efficiency. In particular, solid oxide fuel cells (hereinafter, referred to as “SOFCs”), which operate at temperatures of 1,000° C. or lower, hold promise because of their high reaction rates. SOFCs include a cell structure in which an electrolyte layer containing a solid oxide and two electrodes formed of a ceramic material (sintered body) are integrated together. That is, the cell structure is formed of all the solid elements; thus, SOFCs are easy to handle.
To supply a fuel gas or air to a cell structure, a fuel cell usually includes a gas channel provided in an interconnector adjacent to the cell structure. For example, PTL 1 discloses a method for forming dimples serving as gas channels on an interconnector by, for example, etching.